1. Field of the Invention
This invention relates to a partially or fully implantable hearing system which is provided with a unit for electromechanical or electroacoustic stimulation of the middle ear or inner ear or direct electrical stimulation of the inner ear.
2. Description of Related Art
Here, a xe2x80x9chearing disorderxe2x80x9d is defined as inner ear damage, middle ear damage, combined inner ear and middle ear damage, cochlear deafness which necessitates the use of a cochlear implant, as well as retrocochlear hearing disorders which necessitate the use of a brain stem implant, i.e. in brief, everything which prevents or adversely affects sound pick-up and/or routing to the brain stem.
In recent years, rehabilitation of sensorineural hearing disorders with partially implantable electronic systems has acquired major importance. This applies especially to the group of patients in which hearing has completely failed due to accident, illness or other effects or the group of patients in which hearing has not been functional since birth. If, in these cases, only the inner ear (cochlea) and not the central neural auditory path is affected, electrical signals stimulate the remaining auditory nerve and thus produce a hearing impression which can lead to speech comprehension. In these so-called cochlear implants, an array of stimulating electrodes are inserted into the cochlea and controlled by an electronic system; this hermetically tight and biocompatibly encapsulated electronic module being surgically embedded in the bony area behind the ear (mastoid). The electronic system, however, contains essentially only decoder and driver circuits for the stimulating electrodes. Acoustic sound reception, conversion of this acoustic signal into electrical signals and their further processing, take place basically externally in a so-called speech processor which is worn outside on the body. The speech processor converts the preprocessed signals into a radio frequency carrier signal which is correspondingly coded and transmitted to the implant via inductive coupling through the closed skin (transcutaneously). The sound-receiving microphone is located exclusively outside the body and, in most applications, in a housing of a behind-the-ear hearing aid worn on the external ear. The microphone is connected by a cable to the speech processor. Such cochlear implant systems, their components, and the principles of transcutaneous signal transmission are described, for example, published European Patent Application in EP-A-0 200 321 and in U.S. Pat. Nos. 5,070,535, 4,441,210, and 5,626,629. Processes of speech processing and speech coding in cochlear implants are described, for example, in published European Patent Applications EP-A-0 823 188 and EP-B-0 190 836, and in U.S. Pat. Nos. 5,597,380, 5,271,397, 5,095,904, 5,601,617 and 5,603,726.
In addition to rehabilitation of congenitally deaf persons and those who have lost their hearing using cochlear implants, for some time there have been approaches which offer improved rehabilitation to patients with a sensorineural hearing disorder which cannot be surgically corrected with partially or fully implantable hearing aids or with conventional hearing aids. The principle consists in most embodiments in stimulating an ossicle of the middle ear or the inner ear directly via mechanical or hydromechanical stimulation and not via the amplified acoustic signal of a conventional hearing aid, in which the amplified acoustic signal is supplied to the external auditory canal. The actuator stimulus of these electromechanical systems is accomplished with different physical transducer principles, for example, by electromagnetic and piezoelectric systems. The advantage of these processes is realized mainly in improved tone quality compared to conventional hearing aids and for fully implanted systems in the fact that the hearing prosthesis is not visible. Such partially or fully implantable electromechanical hearing aids are described for example by Yanigahara, et al., in Arch. Otolaryngol. Head Neck Surg, Vol. 113, August 1987, pp. 869-872; Suzuki, et al., in Advances in Audiology, Vol. 4, Karger Basel, 1988; Leysieffer, et al., in HNO, Vol. 46, 1998, pp. 853-863; Zenner, et al., in HNO, Vol. 46, 1998, pp. 844-852, and in numerous patent documents, especially in U.S. Pat. Nos. 5,999,632, 5,277,694, 5,411,467, 3,764,748, 4,352,960, 5,015,224, 5,015,225, 3,557,775, 3,712,962, 4,729,366, 4,988,333, 5,814,095, 4,850,962, 5,859,916, in published European Patent Application EP-B-0 263 254, and published International Patent Applications WO-A-98/36711, WO-A-98/06237, WO-A-98/03035, WO-A-99/08481, WO-A-99/08475, WO-A-99/07436, and WO-A-97/18689.
In all the aforementioned rehabilitation devices, it now seems highly sensible to design the systems such that they can be fully implanted. Depending on the desired function, such hearing systems consist of three or four functional units: (1) a sensor (microphone) which converts the incident airborne sound into an electrical signal, (2) an electronic signal processing, amplifying, and implant control unit, (3) an electromechanical or implantable electroacoustic transducer which converts the amplified and preprocessed sensor signals into mechanical or acoustic vibrations and supplies them via suitable coupling mechanisms to the damaged middle and/or inner ear or a cochlear stimulating electrode in cochlear implants, and (4) an electrical power supply system which supplies the aforementioned modules. Furthermore, there can be an external unit which makes electrical recharging energy available to the implant when the implant-side power supply unit contains a rechargeable secondary battery. Especially advantageous devices and processes for charging of rechargeable implant batteries are described in commonly owned, co-pending U.S. patent application Ser. No. 09/311,566 which is hereby incorporated by reference, and in U.S. Pat. No. 5,279,292. Preferably, there can also be a telemetry unit with which patient-specific audiologic data can be transmitted wirelessly in both directions or programmed in the implant and thus permanently stored, as was described in Leysieffer, et al., in HNO, Vol. 46, 1998, pp. 853-863.
To enable simple updating of the operating software of the implant without surgery, in commonly owned, co-pending U.S. patent application Ser. No. 09/369,182 which is hereby incorporated by reference, it is proposed that the implant electronics be made such that at least parts of the operating program can be altered or replaced by data transmitted from an external unit via a telemetry means which preferably works inductively.
One aspect in hearing systems is their use in conjunction with telecommunication means.
Published International Application WO 98/51124 relates to matching of telecommunication terminal devices such as the mobile part of a cordless phone to hearing systems for rehabilitation of hearing disorders. Here, it has been proposed that the mobile part be equipped with a unit which converts the signal delivered to the speaker of the mobile part, depending on information regarding the hearing system used by the user compared to normal operation for individuals with intact hearing, such that the user of the hearing system acquires a hearing impression as optimum as possible. The hearing aids are conventional electroacoustic devices or a cochlear implant in which the microphone and the speech processor are worn externally behind the external ear. In the latter case, it is proposed that the signal, which is conditioned by the telecommunication terminal device especially for the hearing aid used, be supplied directly to the receiver of the cochlear implant or the implanted electrode wire. For the latter case, the use of a socket or a corresponding bus is being proposed. The disadvantage in this hearing system is that specially modified telecommunication terminal devices must be used to enable the hearing system user to use the telecommunication networks.
U.S. Pat. No. 5,824,022 discloses a cochlear implant system which has an implantable cochlea stimulator and a speech processor unit which is worn behind the ear and which, on the one hand, processes the acoustic signals which are captured via a microphone and transmits them inductively to the implantable cochlea stimulator and, on the other hand, via a radio frequency route can communicate bidirectionally with a remote control which has an audio socket for receiving radio, TV and Walkman audio signals which can be processed by means of an audio processor and can be sent to the speech processor unit.
U.S. Pat. No. 6,021,207 discloses an insert earphone which can be inserted into the auditory canal and which has a microphone and a speaker. The insert earphone is in wireless bidirectional communication with a remote control unit in order to send, on the one hand, the audio signals acquired by the microphone to it and, on the other hand, to receive audio signals from it and output them via the speaker. The remote control can be a mobile phone or a unit connected to it.
Published European Patent Application EP 0 671 818 A1 discloses an RF receiver which, including the battery and earphone, can be arranged in a housing which can be inserted into the auditory canal of an individual.
A primary object of this invention is to devise a partially or fully implantable hearing system which enables its user to easily use telecommunication networks.
This object is achieved in conformity with the invention by a partially or fully implantable hearing system which is directly linkable to telecommunication networks without terminals. In this approach in accordance with the invention, it is advantageous that the hearing system is not linked via the telecommunication terminal devices but that linkage is achieved by a modification of the hearing system itself. Hearing systems linked via the telecommunication terminal devices must be either tuned in a complex manner specially to the hearing system which is being used, or, if this tuning is omitted due to the then absence of tuning between the hearing system and the telecommunication terminal device, such systems allow only poor hearing quality. Furthermore, by modification of the hearing system itself, the use of a telecommunication terminal device in fact is omitted. This entails a major facilitation for the user of the hearing system since he no longer needs to carry this terminal device and thus, for example, has his hands free at all times. In this way, voice messages can also be received in a manner not visible to third parties and particularly inaudibly so that third parties are not disturbed. The acoustic pick-up and the stimulation unit of the hearing system thus functionally replace the corresponding components (microphone and earphone) of a telecommunication terminal device.
Basically the hearing system can also be designed for rehabilitation of a hearing disorder of the user or also for a user without a hearing disorder. In the latter case, an xe2x80x9cinvisible mobile phonexe2x80x9d can be implemented when the system is fully implanted.